Medical bandages with a skin adhesion reducing material

ABSTRACT

A bandage that facilitates the removal of the bandage from the skin is shown and described. The bandage comprises a selectively releasable adhesion reducing material contained in structures such as a selectively rupturable reservoir or a selectively deformable synthetic or natural matrix. When the adhesion reducing material is released from the reservoir, it contacts the bandage&#39;s skin adhesive and reduces its adhesion to the skin.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication No. 61/531,445, filed on Sep. 6, 2011, the entirety of whichis hereby incorporated by reference.

FIELD

The present disclosure relates to bandages, and more particularly, tobandages that include a selectively releasable adhesion reducingmaterial for decreasing the adhesive forces between a bandage and auser's skin and the trauma associated with removing the bandage.

BACKGROUND

Historically, sterile latex free medical strip bandages haveincorporated a liquid absorbent pad comprising a non-stick cottonfabric, plastic or polymer fabric and/or silicon fabric covers wounds, abacking comprising paper, vinyl, cloth and/or plastic “sheer” flexiblezinc oxide, with a skin adhesive such as a hypoallergenic acrylicadhesive for affixing the bandage to the patient's skin to hold theabsorbent pad in proper position over the wound. Moreover, most majorstrip bandage manufacturers such as Band-Aid® use breathable porous orperforated flexible adhesive materials in their bandage strips.Breathable adhesive bandage strips provide greater comfort to patientsby allowing airflow to the skin. Furthermore, conventional stripbandages may be waterproof and offered in a variety of different shapesand sizes depending upon the size and location of the wound on thepatient's body. For example, depending upon the size and the location ofthe wound on the patient's body a strip bandage may be oblong,rectangular, round, triangular, square (etc.) in shape. Bandage sizestypically range from ⅝ in×2¼ in (1.5 cm×5.7 cm), ¾ in×3 in (1.9 cm×7.6cm), 1 in×3 in (2.5 cm×7.6 cm), ⅝ in×2¼ in (1.5 cm×5.7 cm), ¾ in×3 in(1.9 cm×7.6 cm) for skin lesions and minor skin scraps on the body to 1½in×3 in (3.8 cm×7.6 cm) and 1½ in×2 3/16 in (3.8 cm×5.5 cm) for skinlesions and minor skin scraps on the knuckles and fingertips.Conventional strip bandages have also been aesthetically improved bysuperimposing cartoon characters onto the bandages, making bandages glowin the dark, matching bandage colors to patient skin colors and by clearor “see through” bandage strip designs.

Regardless of modern medical strip bandage technology advancements, theproblems associated with removing conventional adhesive strip bandageshave not been solved and continue to be of paramount importance to theindustry. This is because removing adhesive bandage strips is typicallypainful, particularly for children (pediatric) and the elderly(geriatric), and may cause body effacement by removing the patient'shair, and/or causing skin irritations, skin trauma and even skinlesions. According to one report by 3M, “1.5 million patients in U.S.health care facilities receive skin injuries caused by bandage removaleach year.” Presently, doctors often advise patients to lay in warm bathwater and wait for the water to loosen up strip bandages' adhesiveproperties prior to removal. Moreover, an entire strip bandage adhesiveremoval aftermarket product industry has developed around decreasingpatient pain, body effacement, and skin damage such as Smith & Nephew'sUni-Solve Adhesive Remover. Nevertheless, such currently availableaftermarket products are inconvenient and require the bandage wearer toseparately purchase and apply an adhesive remover to a bandage affixedto the skin. One approach has been developed in which bandage backingsare provided with rupturable pockets that include an adhesion reducingmaterial. However this approach may preclude the use of breathable orotherwise permeable backings and can cause undesirable leakage.

As a result, a need has developed for a bandage that addresses theforegoing issues.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a top plan view of a first embodiment of a bandage with anadhesion reducing material contained in a selectively rupturablereservoir attached to the bandage backing;

FIG. 2 is a top plan view of a second embodiment of a bandage with anadhesion reducing material contained in a selectively rupturablereservoir attached to the bandage backing;

FIG. 3 is a top plan view of a third embodiment of a bandage with anadhesion reducing material contained in a selectively rupturablereservoir attached to the bandage backing;

FIG. 4 is a top plan view of a fourth embodiment of a bandage with anadhesion reducing material contained in two selectively rupturablereservoirs attached to the bandage backing;

FIG. 5 is a top plan view of a fifth embodiment of a bandage with anadhesion reducing material contained in a selectively rupturablereservoir attached to the bandage backing;

FIG. 6 is a top plan view of a sixth embodiment of a bandage with anadhesion reducing material contained in two selectively rupturablereservoirs attached to the bandage backing;

FIG. 7 is a perspective view of a seventh embodiment of a bandage withan adhesion reducing material contained in two selectively rupturablereservoirs attached to the bandage backing;

FIG. 8 is top plan view of an eighth embodiment of a bandage with anadhesion reducing material contained in six selectively rupturablereservoirs attached to the bandage backing;

FIG. 9A is a side elevational view of one of the selectively rupturablereservoirs of the bandage of FIG. 7;

FIG. 9B is a top plan view of the reservoir of FIG. 9B;

FIG. 9C is a perspective view of a the reservoir of FIG. 9A;

FIG. 9D is a side cross-sectional view taken along line 9D-9D of FIG.9B;

FIG. 10 is an exploded, side cross-sectional view of an embodiment ofone of the selectively rupturable reservoirs of the bandage of FIG. 7;

FIG. 11 is a side cross-sectional view of the reservoir of FIG. 10 insealed configuration;

FIG. 12 is a side cross-sectional view of the reservoir of FIG. 10 in aruptured configuration;

FIG. 13 is an exploded side cross-sectional view of an alternateembodiment of one of the selectively rupturable reservoirs of thebandage of FIG. 7; and

FIG. 14 is an exploded perspective view of ninth embodiment of a bandagewith an adhesion reducing material contained in two deformable adhesionreducing material matrices from which the material is selectivelyreleasable.

Like reference numerals refer to like parts in the figures.

DETAILED DESCRIPTION

The present disclosure relates to a medical bandage device that includesa selectively releasable adhesion reducing material. The adhesionreducing material is capable of reducing the adhesive forces between thewearer's skin and the bandage, thereby reducing pain and body effacementduring removal. In certain examples, the adhesion reducing material isprovided in one or more self-contained selectively rupturable reservoirsattached to a bandage backing. In other examples, one or more adhesionreducing material matrices impregnated with the adhesion reducingmaterial are attached a bandage backing layer and are selectivelydeformable to release the material.

The adhesion reducing material is preferably a liquid or semi-solidmaterial. Suitable adhesion reducing materials include water, plantextracts, petroleum extracts, and animal extracts. Exemplary plantextracts include olive oil, safflower oil, cotton seed oil, peanut oil,soybean oil, castor oil, sesame oil, aloe vera and eucalyptus oil.Exemplary animal extracts include fatty acids such as those found in emuoil. Exemplary petroleum extracts include petrolatum (petroleum jelly)and mineral oil. One exemplary petrolatum is White Petrolatum USP skinprotectant, which is a semi-solid mixture of hydrocarbons that iscapable of breaking down certain off-the-shelf adhesives, such ascyanoacrylates, which are used in traditional breathable bandages.

Other suitable adhesion reducing materials include many off-the-shelfmedical adhesive solvents designed for removing medical bandages. Theactive ingredients for most of these adhesive solvents are DipropyleneGlycol Methyl Ether, Isoparaffin C10-C11, and Isopropyl Alcohol.

In certain examples described herein, the adhesion reducing material isprovided in at least one selectively rupturable reservoir that isattached to the bandage backing layer such that when the user rupturesthe reservoir, the adhesion reducing material is released from thereservoir. In this context the term “released” refers not only toexamples in which the adhesion reducing material begins to flow freelyonce the reservoir is ruptured, but also those in which the adhesionreducing material becomes accessible to the user and available for theuser to contact and spread over desired locations on the bandage. Inpreferred embodiments, the bandage is breathable, microporous, channeledor in some other way permeable to the adhesion reducing material so thatthe adhesion reducing material can flow over or be applied to thebackside of the bandage backing layer upon release and then migrate tothe opposite side of the backing to make contact with the skin adhesiveand diminish its adhesive forces with the bandage wearer's skin.

As will be discussed further herein, in certain examples, theselectively rupturable reservoir includes a housing and a sealingmembrane. In certain cases, the selective rupturing comprises rupturingthe housing. In other cases, the selective rupturing comprises rupturingthe sealing membrane. In other cases, both the housing and sealingmembrane may be ruptured. In certain examples, the adhesion reducingmaterial is completely self-contained in the selectively rupturablereservoir such that the bandage backing itself does not form part of thereservoir.

In other examples, the medical bandages described herein include anadhesion reducing material layer or section, in the form of a syntheticor natural matrix (e.g., a film, foam, or gauze) that is distinct fromthe backing itself and capable of absorbing and retaining the adhesionreducing material until deformed by a user to cause the material to bereleased.

Referring to FIG. 1, a first example of a medical bandage 20 with aselectively releasable adhesion reducing material (not visible) isdepicted. Medical bandage 20 may be used in a wide variety ofapplications and includes adhesive strip bandages, adhesive gauze,adhesive tapes, adhesive nasal dilators, and butterfly wound closingbandages.

The backing layer 22 includes two surfaces 28 (facing the viewer inFIG. 1) and 30 (facing away from the viewer in FIG. 1). Bandage 20includes an absorbent pad region 26 b and two skin adhesive regions 26 aand 26 c. The regions define particular locations along the length axisdirection L and width axis direction W of bandage 20. The absorbent padregion 26 b corresponds to the locations along the length L and width Waxes where an absorbent pad 32 is present on lower surface 30 of backinglayer 22. Skin adhesive regions 26 a and 26 c correspond to locationsalong the length L and width W axes where a skin adhesive is found onthe lower surface 30 of backing layer 22. The two skin adhesive regions26 a and 26 c are spaced apart from one another along the bandage lengthaxis direction L such that the absorbent pad region 26 b is locatedbetween first and second skin adhesive regions 26 a and 26 c.

Backing layer 22 may be comprised of a number of materials, includingpaper, woven or non-woven cloths, ETS (a special fabric that is elasticin only one direction) or plastic films. Composites of polymeric filmswith woven or non-woven cloths may also be used. Exemplary plastic filmsinclude polyethylene, polyurethane, polyolefin, EVA (ethylene vinylacetate), Coflex (a latex free elastic material commonly used forbandage backings) and polyvinyl chloride films. In preferred examples,backing layer 22 is permeable to an adhesion reducing material so thatthe material may migrate from one side of the backing to the other. Manybandage backings are breathable to facilitate wound healing and watervapor transport from the user's skin which provides a pathway for suchmigration.

Lower surface 30 of backing layer 22 includes a skin adhesive coatingthat defines length L and width W dimensions corresponding to skinadhesive regions 26 a and 26 c. The skin adhesive coating preferablycomprises a skin compatible, medical grade pressure sensitive adhesive.Suitable adhesives include acrylic-based, dextrin based, and urethanebased adhesives as well as natural and synthetic elastomers. Suitableexamples include amorphous polyolefins (e.g., including amorphouspolypropylene), Kraton® Brand synthetic elastomers, and natural rubber.Other exemplary skin adhesives include cyanoacrylates, hydrocolloidadhesives, hydrogel adhesives, and soft silicone adhesives. The skinadhesive coating may also include additives such as tackifiers,anti-oxidants, processing oils, and the like. The adhesive may beapplied to backing surface 30 in any desired manner, including withoutlimitation, spraying, screen printing, or slot die coating. In certainexamples, typical skin adhesive coating weights range from about 20grams/m² to about 100 gram/m².

Lower side 30 of backing layer 22 is attached to an absorbent pad 32within absorbent pad region 26 b. During normal use, the absorbent pad32 contacts a local skin trauma such as a wound, scrape, abrasion,laceration, etc. on the wearer's body, while the regions 26 a and 26 con backing side 30 contact the wearer's skin, preferably without alsocontacting the local skin trauma. Suitable absorbent pads include cottongauzes, and/or combinations of cotton and/or gauze with plastic films,such as those described as being suitable for backing layer 22, above.In those adhesively affixed medical bandages or devices that are notused for wound care or protecting skin trauma areas, the absorbent pad32 may be excluded.

A selectively rupturable reservoir 24 is disposed on upper surface 28 ofbacking layer 22. Selectively rupturable reservoir 24 includes a housing25 that projects toward the viewer in a direction away from bandagebacking layer surface 28 (i.e., orthogonally to the L and W axes in FIG.1). Selectively rupturable reservoir 24 also includes a sealing membrane(not visible in FIG. 1) that is disposed on the upper surface 28 ofbacking layer 22. The housing 25 and the sealing member are configuredto create an enclosed space that contains an adhesion reducing materialof the type described previously. The sealing membrane is preferably athin film that is impermeable to the adhesion reducing material.Suitable sealing membrane materials include thin, flexible polyethylenematerials such as LDPE materials. Commercially available LDPE films areoften used as membrane, release liners, laminates, etc. and aresometimes supplied with a layer of release coating, such as in the caseof siliconized LDPEs or other with layers of other adhesives. Filmssuitable as sealing membrane materials include LF 444 LDPE, OPTILiner®,and SUPRALiner® release liners, supplied by Saint-Gobain PerformancePlastics. Other suitable release liners include Silthene® Siliconecoated polyethylene and SilProp® Silicone coated polypropylene, suppliedby 3M as well as 3M Easy Release Liner Unapplied 33, 3M Non-SiliconeRelease Liners 4935, 3M Secondary Liner-Non-Silicone 5932, 3M SecondaryLiner—Non-Silicone 5932, 3M Silicone Release Liners 4988, 3M SiliconeRelease Liners 4996, and 3M Silicone Release Liners 4999. Other suitablefilms include polystyrene, polyethylene terephthalate, polyester,polyurethane, Mylar, Melinex, Hostaphan, silicone films, andpolyolefins.

In FIG. 1, the selectively rupturable reservoir 24 is a single reservoirhaving a profile (when viewed in top plan view) which correspondssubstantially to the profile of the outer edge of the bandage 20. Aswill be seen in subsequent examples, a wide variety of top plan viewprofiles may be used, and the one depicted in FIG. 1 is merelyexemplary. The selectively rupturable reservoir 24 is preferablyself-contained, i.e., the bandage backing does not form part of thereservoir 24 or its internal enclosure, to better ensure that theadhesion reducing material is not prematurely released or subject toleakage. A cross-sectional view of the housing 25 and the sealingmembrane will be described below with reference to FIGS. 10 and 13.

The housing 25 is preferably comprised of a generally rigid plasticmaterial than can be ruptured by pulling a pull tab 34 attached to astring that engages the housing 25. Housing 25 may also include one ormore score lines 36, comprising a thinned area of housing 25 thatfacilitates rupturing at a defined location. Suitable housing plasticsinclude polyethylenes such as low density polyethylene (LDPE), linearlow density polyethylene (LLDPE), medium density polyethylene (MDPE),high density polyethylene (HDPE), ultra high molecular weightpolyethylene (UHMWPE), thermosoftening plastics, silicones, andpolyesters. One suitable LDPE material is a R108000 supplied bySaint-Gobain Performance Plastics.

The housing 25 is preferably sized to accommodate a desired amount ofadhesion reducing material. In certain examples, the amount of adhesionreducing material corresponds to a selected volume of the materialdivided by the surface area of the backing side 30 lying within the skinadhesive regions 26 a and 26 c, i.e., the area of the upper surface 28of backing layer 22 which lies over skin adhesive applied to lowersurface 30 of backing layer 22. In certain examples, the volume ofadhesion reducing material in selectively rupturable reservoir 24 perunit surface area is preferably at least about 1.2 μl/cm², morepreferably at least about 1.8 μl/cm², and still more preferably at leastabout 2.0 μl/cm². At the same time or in other examples, the volume perunit surface area is preferably not more than about 4.6 μl/cm², morepreferably not more than about 3.4 μl/cm², and still more preferably notmore than about 2.5 μl/cm². In one example, the volume of adhesionreducing material per unit surface area of backing side 30 in the skinadhesive regions 26 a and 26 c is about 2.3 μl/cm². In those examplesusing multiple reservoirs (e.g., as shown in FIGS. 4-6, 7 and 8), thetotal amount of desired adhesion reducing material per unit of surfacearea is preferably evenly allocated among the multiple reservoirs.

The pull string (not shown) attached to pull tab 34 may be embedded inthe housing 25 material or otherwise affixed to an internal surface ofthe housing 25 (such as by adhesively bonding the string to an innersurface of the housing 25). Pull tab 34 is sized for gripping by abandage wearer. Pull tab 34 may be formed from a fabric, plastic or anyother sturdy, grippable material. A pull string may also be embedded inthe housing proximate score line 36 (if provided).

A method of using the removing bandage 20 from a wearer's skin will nowbe described. Bandage 20 is applied to the wearer's skin with absorbentpad 32 in contact with a skin trauma such as a wound, abrasion, rash,laceration, ulcer, etc. The skin adhesive on lower surface 30 of backinglayer 22 (which lies within the boundaries of skin adhesive regions 26 aand 26 c) is adhered to the wearer's skin on either side of the skintrauma. After a period of use (e.g., one day, two days, one week, twoweeks, etc.) the wearer may desire to remove the bandage 20 from his orher skin. At that point, the wearer grips pull tab 34 and pulls it torupture housing 25, thereby exposing the adhesion reducing materialcontained in the selectively rupturable reservoir 24 and making itaccessible to the wearer. In certain cases, the viscosity of theadhesive reducing material will cause the material to flow over uppersurface 28 of backing layer 22 quickly after the housing 25 is ruptured.In other cases, and depending especially on the viscosity of theadhesion reducing material, the wearer may need or want to manuallyspread the adhesion reducing material across the upper surface 28 ofbacking layer 22 in order to contact a desired amount of the surfacearea of the backing layer 22 surface 28. Even in those cases where theadhesion reducing material tends to flow out of the ruptured housing 25,the user may wish to spread it across the portion of the upper surface28 of the backing layer 22 that lies within the skin adhesive regions 26a and 26 c to maximize the area of contact between the skin adhesive andthe adhesion reducing material. Once in contact with the upper surface28 of backing layer 22, the adhesion reducing material preferablymigrates through the backing layer 22 from upper surface 28 to lowersurface 30 to contact the skin adhesive and diminish the adhesive forcesbetween the backing layer 22 and the wearer's skin. The wearer can thengrip and peel the backing layer 22 from the skin with reduced pain andbody effacement than would otherwise occur without the adhesion reducingmaterial.

Referring to FIG. 2, another example of a bandage comprising aselectively releasable adhesion reducing material is depicted. Like thebandage 20 of FIG. 1, bandage 21 of FIG. 2 includes a selectivelyrupturable reservoir 38 affixed to backing layer 22 surface 28 ofbandage 21. The only significant difference between the bandage 21 ofFIG. 2 and that of FIG. 1 is in the profile of the selectivelyrupturable reservoir 38. Selectively rupturable reservoir 38 extendsonly along the length axis direction L of bandage 20. Pull tab 34 isprovided and is attached to a string or fabric (not shown) that engagesthe reservoir housing 25 such that when user pulls the pull tab 34, thereservoir housing 25 ruptures. In the case of bandage 20, theselectively rupturable reservoir 38 runs along the longitudinal midlineof the backing layer 22 along essentially the entire length of bandage21 such that the reservoir 38 crosses the absorbent pad region 26 b andwell as the skin adhesive regions 26 a and 26 c. In certain examples,the amount of the adhesion reducing fluid contained in the selectivelyrupturable reservoir 38 is the same per unit surface area of the uppersurface 28 of backing layer 22 lying in the first skin adhesive region26 a and second skin adhesive region 26 c as described previously withrespect to FIG. 1.

Referring to FIG. 3, a third example of a bandage with a selectivelyreleasable adhesion reducing material is depicted. Bandage 23 is similarto bandages 20 and 21, except as to the top plan view profile of theselectively rupturable reservoir 40. Selectively rupturable reservoir 40comprises a plurality of linear segments, 42 a, 42 b, 42 c, 42 d, and 42e. The plurality of linear segments comprises a first subplurality oflinear segments 42 a, and 42 e which extend along the longitudinalmidline of the bandage backing layer 22 in the direction of the backinglength axis L. A second subplurality of linear selectively rupturablereservoir segments 42 b and 42 d extends along the direction of thebacking width axis W, starting from a point at the longitudinal midlineof the bandage 23 and extending to a point proximate the width-wise edgeof the bandage 23. Segment 42 c extends along the length axis directionL but is positioned so as to lie outside the absorbent pad region 26 b(i.e., the portion of the backing layer 22 lying immediately aboveabsorbent pad 32).

In the example of FIG. 3, the first and second skin adhesive regions 26a and 26 c are connected by two thin backing regions between which theabsorbent pad 32 lies. Pull tab 34 and string (not shown) are againprovided to allow a user to selectively rupture the selectivelyrupturable reservoir 40 in the same manner described previously withrespect to FIGS. 1 and 2. The pull tab 34 and string are preferablyconfigured so that the wearer can rupture each linear segment 42 a-42 eof the selectively rupturable reservoir 40. The reservoir 40 has thesame components (a housing and sealing membrane) and cross-sectionalprofile as the corresponding reservoirs 24 and 38 of FIGS. 1 and 3. Thecross-sections will be illustrated and described below with reference toFIGS. 10 and 13. In certain examples, the amount of the adhesionreducing fluid contained in the selectively rupturable reservoir 40 isthe same per unit surface area of the upper surface 28 of backing layer22 lying in the first skin adhesive region 26 a and second skin adhesiveregion 26 c as described previously with respect to FIG. 1.

Referring to FIG. 4, a fourth example of a bandage comprising aselectively releasable adhesion reducing material is depicted. In theexample of FIG. 4, bandage 27 comprises two selectively rupturablereservoirs 44 a and 44 b. Each selectively rupturable reservoir 44 a and44 b includes a corresponding one of housing 25 a and 25 b and acorresponding sealing membrane (not shown) attached to the backing. Eachselectively rupturable reservoir 44 a and 44 b may also include acorresponding score line 36 a and 36 b to facilitate rupturing of thecorresponding hosing 25 a and 25 b.

Selectively rupturable reservoir 44 a is linear in top plan view profileand extends along the direction of the length axis L of the bandagebacking layer 22. The reservoir 44 a is positioned substantially at thelongitudinal midline of bandage backing layer 22. Pull tab 46 a and acorresponding string (not shown) are provided to allow the wearer toselectively rupture reservoir 44 a along its length.

Selectively rupturable reservoir 44 b is also linear in profile andextends along the length axis direction L of the bandage backing layer22. The reservoir 44 b is also positioned substantially at thelongitudinal midline of backing layer 22. Pull tab 46 b and acorresponding string (not shown) are provided to allow the wearer toselectively rupture reservoir 44 b. The reservoirs 44 a and 44 b arespaced apart from one another in the length axis direction L of thebandage. Reservoir 44 a is located within the first skin adhesive region26 a of bandage 27, and reservoir 44 b is located within the second skinadhesive region 26 c of bandage 27. The absorbent pad region 26 b of thebandage backing layer 22 lies between the first and second selectivelyrupturable reservoirs 44 a and 44 b. The interiors of reservoirs 44 aand 44 b are not in fluid communication with one another. The reservoirs44 a and 44 b are preferably constructed in the same fashion as thereservoirs 24, 38, and 40 of FIGS. 1-3. The reservoir profile andconfiguration of bandage 27 allows the wearer to selectively andindividually reduce the adhesion of one of the skin adhesive regions 26a and 26 c by pulling the tab of the respective reservoir and allowingthe adhesion reducing material to flow over the backing layer 22 and/orby spreading the adhesion reducing material over the backing layer 22 sothat it migrates through the portion of backing layer 22 lying withinwhich ever region 26 a or 26 c is selected and makes contact with thatregion's skin adhesive. In certain examples, the total amount of theadhesion reducing fluid contained in the selectively rupturablereservoirs 44 a and 44 b is the same per unit surface area of the uppersurface 28 of backing layer 22 lying in the first skin adhesive region26 a and second skin adhesive region 26 c as described previously withrespect to FIG. 1. The adhesion reducing material may preferably bedistributed evenly between reservoirs 44 a and 44 b.

Referring to FIG. 5, a fifth example of a bandage comprising selectivelyreleasable adhesion reducing material is depicted. In the example ofFIG. 5, bandage 35 comprises a single selectively rupturable reservoir48 comprising a plurality of linear segments 50 a, 50 b, and 50 c.Linear segments 50 a and 50 c comprise a plurality of linear segmentsextending along the width axis direction W of the bandage backing layer22. Selectively rupturable reservoir segment 50 b connects segments 50 aand 50 c and extends along the length axis direction L of the bandagebacking layer 22. Bandage backing layer 22 has two backing strips thatextend in the length axis direction L alongside the absorbent pad region26 b, and segment 50 b extends through one of the backing strips whilestill laying outside of the absorbent pad region 26 b (i.e., the segment50 b does not lie above the absorbent pad 32).

Selectively rupturable reservoir segments 50 a and 50 c are respectivelylocated in skin adhesive regions 26 a and 26 c of backing layer 22 andare also connected to corresponding ends of segment 50 b. The interiorsof the selectively rupturable reservoir segments 50 a-50 c are in fluidcommunication with one another. Pull tab 52 is provided and ispreferably connected to a string (not shown) that allows the user torupture the housing 25 of selectively rupturable reservoir 48 along eachof its segments 50 a-50 c. The selectively rupturable reservoir 48 ispreferably constructed in the same manner as the reservoirs 24, 38, 44a, and 44 b of FIGS. 1-4. In certain examples, the amount of theadhesion reducing fluid contained in the selectively rupturablereservoir 48 is the same per unit surface area of the upper surface 28of backing layer 22 lying in the first skin adhesive region 26 a andsecond skin adhesive region 26 c as described previously with respect toFIG. 1.

Referring to FIG. 6, a sixth example of a bandage comprising aselectively releasable adhesion reducing material is depicted. Bandage37 comprises two selectively rupturable reservoirs 56 a and 56 b, eachof which extends along the width axis direction W of the bandage backinglayer 22. Each selectively rupturable reservoir 56 a and 56 b comprisesa corresponding selectively rupturable housing 25 a and 25 b and acorresponding sealing member (not shown) attached to the upper surface28 of the backing layer 22. The two selectively rupturable reservoirs 56a and 56 b are spaced apart from one another in the length axisdirection L of bandage backing layer 22, and their respective interiorsare not in fluid communication with one another. Pull tab 60 a isconnected to a string (not shown) and may be used to selectively rupturethe housing 25 a of reservoir 56 a. Pull tab 60 b is similarly providedwith a string (not shown) for selectively rupturing reservoir 56 b. Aswith bandage 27 of FIG. 4, a wearer can selectively reduce the adhesiveforces of either bandage skin adhesive region 26 a or 26 c towards thewearer's skin by rupturing the corresponding selectively rupturablereservoir 56 a or 56 b. The selectively rupturable reservoirs arepreferably constructed in the same manner as the reservoirs 24, 38, 44a, 44 b, and 48 of FIGS. 1-5.

A method of making the bandages of FIGS. 1-6 will now be described. Inaccordance with a first exemplary method, sheets of material used toform backing layer 22 are provided and are coated with a skin adhesiveon one side (the side corresponding to lower surface 30 of backing layer22). The backing layer material is then cut into strips and theabsorbent material used to form absorbent pads 32 is cut into strips.Using standard bandage making machinery, the absorbent pad materialstrips are adhesively adhered to a central portion of the strips ofbacking layer 22 material such that there is a portion of backing oneither side of the absorbent pad strips. The backing portions on eitherside of the absorbent pad strips will eventually comprise the first andsecond skin adhesive regions 26 a and 26 c of the finished bandages. Incertain examples, form fill seal equipment or equivalent tooling is usedto fill and seal the reservoirs which are formed from the materialsdescribed above for housing 25 and the sealing membrane.

The material used to form the housing 25 of the selectively rupturablereservoirs (e.g., an LDPE material used to form the housings ofreservoirs 24, 38, 40, 44 a, 44 b, 48, 56, 58) is shaped using heat(e.g., heat rollers that form dimples of desired dimensions) and/orpressure and cut to create a cross-sectional profile such as that ofhousing 65 a in FIGS. 10 and 11 and the desired top plan view profile(e.g., one of the profiles in FIGS. 1-6). Thus, in the case ofreservoirs 24, 38, 40, 44 a, 44 b, 48, 56, and 58, each housing includesa central domed portion and two side flanges. The central domed portioncorresponds to reference numeral 66 a in FIGS. 10 and 13 and has flangeson either side. In FIGS. 10 and 13 the flanges are shown as a singleflange 68 a because FIG. 10 is used to illustrate a circular reservoir(as discussed below) In the case of the reservoirs of FIGS. 1-6, thereservoir top plan view profile is not circular, so each housing 25would include two flanges on either side of a central domed portion whenviewed in cross-section.

The housings 25 are then filled with the adhesion reducing material, andstrips of the sealing membrane material are placed over the open face ofthe housing such that the outer periphery of the sealing strips islocated inward of the outer-most part of the flanges. This configurationallows the flanges to directly attach to the backing and sandwich thesealing membrane periphery between the flanges and the backing.

The strips of backing material are then coated with a housing adhesivein the desired pattern, and the housing, sealing membrane, and backingstrips are assembled together such that the housing is adhesivelyattached to the backing strips and a portion of the periphery of thesealing membrane is sandwiched between the periphery of the housing andthe bandage backing, as will be discussed further below with referenceto FIGS. 10-13. Once the housings, backing strips, and sealing membranesare thusly assembled, the assembly can be cut to the desired shape andsize to yield the bandage. In preferred examples, one or more releaseliners with a release coating will be placed over the skin adhesive toprotect it prior to use, and the bandages will be packaged andsterilized using known techniques. The packaging and sterilizationtechniques are preferably selected to maintain the integrity of thereservoirs and the adhesion reducing material.

In accordance with another method of making the bandages of FIGS. 1-6,manufacturing, the strips of sealing membrane material may be suppliedas a bulk double-sided adhesive film with adhesive coatings on bothsides. The double sided adhesive film would then be applied to the sideof the backing material strips that is opposite the side on which theabsorbent pad material strips are disposed. Depending on the particularselectively rupturable reservoir top plan view profile, it may bedesirable or necessary to cut the double sided adhesive film into adesired shape before placing it on the backing material strips. Once thedouble sided adhesive film is attached to the backing, the backing canbe applied to the liquid filled housings to seal the adhesion reducingmaterial within the enclosure defined by the housings and the sealingmembrane material (i.e., the double-sided adhesive film). Thehousing/film/backing/absorbent pad strips can be cut to the desiredshape of the finished bandage. Suitable double-sided adhesive filmsinclude double sided adhesive tapes supplied by 3M. The use of suchdouble-sided adhesive films avoids the need for a separate step to applyan adhesive to the backing.

The selectively rupturable reservoirs of FIGS. 1-6 each include one ormore linear reservoir segments. However, a variety of reservoirgeometries may be used, both regular and irregular. Referring to FIG. 7,a seventh example of a bandage comprising a selectively releasableadhesion reducing material is depicted. In this example, bandage 33comprises two selectively rupturable reservoirs 64 a and 64 b, each ofwhich have a circular profile when viewed from a top plan view (i.e.,orthogonally to the length L and width W axes of the backing layer 22).Selectively rupturable reservoirs 64 a and 64 b each include acorresponding housing 65 a and 65 b. Housing 65 a comprises radiallyinward dome 66 a and a radially outward flange 68 a. Housing 65 bcomprises a radially inward dome 66 b and a radially outward flange 68b.

FIGS. 9A-9D are representative of selectively rupturable reservoir 64 balthough only reservoir 64 a is specifically depicted. FIG. 9A providesa side elevational view of selectively rupturable reservoir 64 a.

FIG. 9B provides a top plan view of the selectively rupturable reservoir64 a, while FIG. 9 c provides a perspective view of the reservoir 64 a.A side cross-sectional view of selectively rupturable reservoir 64 a isprovided in FIG. 9D. As shown in FIG. 9D, the selectively rupturablereservoir 64 a includes housing 65 a and sealing membrane 70 a.Together, housing 65 a and sealing membrane 70 a define an enclosedinterior space that contains an adhesion reducing material of the typedescribed previously. In FIG. 9D the adhesion reducing material is notshown. As with the previous examples of a selectively rupturablereservoir, the selectively rupturable reservoirs 64 a and 64 b arepreferably self-contained, such that that the bandage backing does notdefine part of the reservoir. In contrast to structure in which abandage backing defines part of a reservoir, self-contained reservoirspreferably reduce premature leakage or unintended release of theadhesion reducing material until bandage removal is desired.

In certain examples, the selectively rupturable reservoirs 64 a and 64 bof FIGS. 7-13 are configured to rupture differently than the selectivelyrupturable reservoirs of FIGS. 1-6. In accordance with such examples,the housings 65 a and 65 b are selectively depressible to cause theirrespective sealing membranes 70 a and 70 b to rupture and release theadhesion reducing material contained within them. In the example of FIG.7, the domes 66 a and 66 b are depressible. In certain examples, thehousings are formed of a depressible plastic. Exemplary plastics includepolyethylenes, including without limitation LDPE, LLDPE, MDPE, HDPE, andUHMWDPE. The thickness and properties of the material used to formhousings 65 a and 65 b and sealing membranes 70 a and 70 b arepreferably selected such that depression of the housing domes 66 a and66 b ruptures the corresponding sealing membranes 70 a and 70 b insteadof the housings 65 a and 65 b themselves.

FIG. 10 provides an exploded cross-sectional view of a oneimplementation of selectively rupturable reservoir 64 a and the backinglayer 22 to which it is attached. In this implementation, a suitablehousing adhesive 29 is applied across the upper surface 28 of backinglayer 22 in a pattern that extends radially outward from the centerlineof dome 66 a to a portion or the edge of flange 68 a. Suitable housingadhesives include cyanoacrylates, 2-octyl cyanoacrylate, and permanentacrylics. Suitable commercially available housing adhesives includeDymax® 222 Series cyanoacrylate, 3M Scotch-Weld Medical Gradecyanoacrylate/instant adhesive and 3M Scotch-Weld™ MG20 SF, 3MScotch-Weld™ MG100 SF, 3M Scotch-Weld™ MG05 PR, 3M Scotch-Weld™ MG1500PR, 3M Scotch-Weld™ MG05 LO, 3M Scotch-Weld™ MG100 LO, and 3MScotch-Weld™ MG300 FLX, as well as Henkel's Loctite® 4011 Prism InstantAdhesive, Loctite® 4061 Prism Instant Adhesive, Loctite® 4014 PrismInstant Adhesive, and Loctite® 4035 Prism Instant Adhesive). Sealingmembrane 70 a is circular and extends from dome 66 a centerline to alocation that is radially outward of dome 66 a and radially inward ofthe outer perimeter flange 68 a. The housing 65 a is affixed to bandagebacking upper surface 28 such that the flange 68 a bonds to the housingadhesive 29 coated on backing upper surface 28, thereby sandwiching aportion of outer periphery of sealing membrane 70 a between flange 68 aand backing layer 22 upper surface 28. In addition, the sealing membrane70 a bonds to the housing adhesive 29 located along the backing layer 22upper surface 28 radially inward of flange 68 a. Adhesion reducingmaterial 72 a is thus contained between the inner surface of dome 66 aand sealing membrane 70 a and isolated from backing layer 22 until beingselectively released by the wearer.

In certain examples, the housing adhesive 29 is selected so as not todegrade or lose its adhesion when contacted by adhesion reducingmaterial 72 a. In accordance with such examples, the adhesion reducingmaterial 72 a selectively and preferentially reduces the skin adhesionof the skin adhesive coated on backing side 30 relative to the adhesionof the housing adhesive 29 to the backing layer 22 and flange 68 a. Theuse of an adhesion reducing material that is formulated in this mannerbetter ensures that the selectively rupturable reservoir 64 a willremain intact while still reducing the adhesion of the skin adhesive tothe wearer's skin.

The housing adhesive 29 may be applied in patterns other than the oneillustrated in FIG. 10. Referring to FIG. 13, the housing adhesive 29 isapplied in an annular pattern, such that the lower side (facing backingupper surface 28) of sealing membrane 70 a does not contact the housingadhesive 29. In this example, flange 68 a and upper surface 28 ofbacking layer 22 are adhesively attached by the annular pattern ofhousing adhesive 29. An outer annular portion of sealing membrane 70 ais sandwiched between flange 68 a and backing layer 22 upper surface 28to hold the sealing membrane 70 a in place within reservoir 64 a. Theannular pattern of FIG. 13 advantageously avoids contact between thehousing adhesive 29 and the sealing membrane 70 a which may impede therupturing of the sealing membrane 70 a when desired. In another example,the sealing membrane 70 a is provided as a double-sided adhesive film ofthe type described previously. The double-sided adhesive film is cut tothe desired membrane 70 a geometry and dimensions and then applied tothe backing layer 22. The backing layer 22 with the applied membrane 70a is then placed over reservoirs 64 a (after filling them with theadhesion reducing material 72 a). Commercially-available double-sidedadhesive tapes of the type described previously may be used to providethe double sided adhesive film. FIGS. 10 and 13 show the membrane film70 a separate from the housing adhesive 29. However, when double-sidedadhesive films are used, the membrane film 70 a and adhesive 29 would beprovided as an integral composite structure which is then adhered tobacking layer 22 and the flange 68 a. In certain preferred examples, ifa double-sided adhesive film is used to form sealing membrane 70 a, themembrane 70 a will extend radially at least as far as the outerperimeter of the reservoir flange 68 a so that the entire flange 68 a issecurely adhered to the membrane 70 a.

In addition or as an alternative to the use of housing adhesive 29, thehousing 65 a may be heated and pressed against backing layer 22 to causethe housing 65 a material to bond to the backing layer 22 material.

The use of bandage 33 (FIG. 7) comprising selectively rupturablereservoirs 64 a and 64 b will now be illustrated with reference to FIGS.11 and 12. Bandage 33 is adhered to a wearer's arm with absorbent pad 32placed in contact with a skin trauma, such as a wound, scrape, ulcer,etc. and the skin adhesive located in skin adhesive regions 26 a and 26c on lower backing surface 30 in contact with the wearer's skin, oneither side of the skin trauma. At this point, when viewed incross-section, the selectively rupturable reservoir 64 a is in a sealedcondition as depicted in FIG. 11, with the adhesion reducing materialsecurely contained within the enclosed space defined between the innersurface of housing dome 66 a and sealing membrane 70 a.

After a period of use the wearer decides to remove the bandage 33 fromhis or her skin. The wearer selects one of the selectively rupturablereservoirs 64 a and 64 b to use first. In this example, reservoir 64 ais selected. As shown in FIG. 12 the wearer then depresses housing dome66 a with one of his or her fingers. Because the housing 65 a containsthe adhesion reducing fluid, the depressive force applied to dome 66 awill cause the adhesion reducing material to apply a force to thesealing membrane 70 a. As shown in FIG. 12, the sealing membrane 70 aruptures in response to the applied force, thereby providing a pathwayfor the adhesion reducing material 72 a to migrate through backing layer22 from upper surface 28 to lower surface 30 (which is coated with askin adhesive). The interaction of the adhesion reducing material 72 aand the skin adhesive reduces the adhesive forces between lower backingsurface 30 and the wearer's skin, which allows the wearer to peel theportion of backing layer 22 within skin adhesive region 26 a.

In certain examples, and depending on the viscosity of the adhesionreducing material 72 a, the depression of the dome 66 a will causeadhesion reducing material 72 a to be squeezed out radially from theruptured reservoir 64 a, causing it to migrate from the lower surface 30to the upper surface 28 of backing layer 22. The wearer can then spreadthe adhesion reducing fluid across the skin adhesive regions 26 a ofbacking upper surface 28, allowing it to migrate back through backinglayer 22 to lower backing surface 30 where it contacts a fuller area ofthe skin adhesive in the bandage's skin adhesive region 26 a. The wearercan then repeat the process for selectively rupturable reservoir 64 b toreduce the adhesion between the skin adhesive in skin adhesive region 26c of backing layer 22 and the wearer's skin. After giving the adhesionreducing material 72 a and 72 b (not shown) sufficient time to weakenthe adhesive forces of the skin adhesive, the wearer can grip an end ofbacking layer 22 and peel off the bandage 33.

A method of making the bandage 33 of FIGS. 7 and 10-13 will now bedescribed. In accordance with a first exemplary method, sheets ofmaterial used to form backing layer 22 are provided and are coated witha skin adhesive on one side (the side corresponding to backing layer 22lower surface 30 in FIGS. 10 and 13). The backing layer material is thencut into strips and the absorbent material used to form absorbent pads32 (not shown in FIGS. 7-13) is cut into strips. Using standard bandagemaking machinery, the absorbent pad material strips are adhesivelyadhered to a central portion of the strips of backing layer 22 materialsuch that there is a portion of backing on either side of the absorbentpad strips. The portions of the backing strips on either side of theabsorbent pad strips will ultimately be the first skin adhesive region26 a and the second skin adhesive region 26 c.

The material used to form the housing 65 a, 65 b of the selectivelyrupturable reservoirs 64 a, 64 b (e.g., an LDPE material) is shapedusing heat (such as heat rollers that form dimples) and/or pressure andcut to create a cross-sectional profile such as that of housing 65 a inFIGS. 10 and 11 and the desired top plan view profile (e.g., FIG. 9B).The housings 65 a and 65 b are then filled with the adhesion reducingmaterial 72 a, 72 b and strips of the sealing membrane material used toform sealing membranes 70 a and 70 b are placed over the open face ofthe housings 65 a, 65 b. The strips of backing material used to formbacking layer 22 are then coated with an housing adhesive in the desiredpattern (e.g., the circular pattern of housing adhesive 29 in FIG. 10 orthe annular pattern of adhesive 31 in FIG. 13), and the housings 65 a,65 b, sealing membrane strips, and backing strips are assembled togethersuch that the housing is adhesively attached to the backing strips and aportion of the periphery of the sealing membrane is sandwiched betweenthe periphery of the housing and the bandage backing, as best seen inFIGS. 10-13. The assembled bandage is then cut to the desired shape(e.g., the shape of FIG. 7). Release liner(s) with a suitable releasecoating are placed over the skin adhesive (not shown) on backing side30, and the bandages are packaged and sterilized. In certain examples,form fill seal equipment or equivalent tooling is used to fill and sealthe reservoirs 64 a and 64 b.

In addition to the foregoing method, an alternate method of making thebandage 33 may be used in which the material used to make sealingmembrane 70 a is provided as a bulk double-sided adhesive film (i.e., afilm with an adhesive coating on both sides). The commercially availabledouble sided adhesive tapes described previously may be provided. In oneexample, the double sided adhesive tape is cut into the desired size andshape of the sealing membranes 70 a and 70 b and applied to the backingmaterial strips, on the side opposite the side on which the absorbentpad material is disposed. After filling the housings 65 a and 65 b withadhesion reducing material 72 a and 72 b, the composite strips of doublesided adhesive film, backing material and absorbent pad are secured overthe filled housings and the final bandages are cut to the desired shapeand size.

Referring to FIG. 8, a modified version of bandage 33 of FIG. 7 isshown. Bandage 39 includes the same backing, skin adhesive, andabsorbent pad structure of the bandage 33 of FIG. 7. However, it alsoincludes six (6) selectively rupturable reservoirs 74 a-c and 76 a-c.Each selectively rupturable reservoir 74 a-c and 76 a-c has the samestructure as selectively rupturable reservoirs 64 a and 64 b of FIG. 7.However, reservoirs 74 a-c are aligned at a common position along thelength axis direction L of the backing layer 22 and are spaced apartfrom one another along with width axis direction W of the backing layer22. Correspondingly, selectively rupturable reservoirs 76 a-c arealigned at a common position along the length axis direction L of thebacking layer 22 and are spaced apart from one another along the widthaxis direction W of the backing layer 22. The first plurality ofselectively rupturable reservoirs 74 a-c is spaced apart from the secondplurality of selectively rupturable reservoirs 76 a-c along the lengthaxis direction L of the backing layer 22. The total amount of adhesionreducing material held in all six (6) selectively rupturable reservoirs74 a-c and 76 a-c per unit surface area of backing layer 22 uppersurface 28 lying in the skin adhesive regions 26 a and 26 c ispreferably the same as described above for the embodiment to of FIG. 7.In certain examples, the total amount of adhesion reducing material issubstantially equally allocated among all six (6) selectively rupturablereservoirs 74 a-c and 76 a-c.

As indicated previously, the cross-sectional profiles of the selectivelyrupturable reservoirs 24, 38, 40, 48, 44 a, 44 b, 56, and 58 of FIGS.1-6 preferably conform to the cross-sectional profile of the reservoir64 a shown in FIGS. 10-13 when viewed along a direction parallel to thelength of the particular reservoir or linear reservoir segment, eventhough they would not appear circular when viewed in a top plan view. Inaddition, the housings and sealing membranes used in selectivelyrupturable reservoirs 24, 38, 40, 48, 44 a, 44 b, 56, and 58 of FIGS.1-6 may be constructed and configured in a similar fashion as describedfor reservoirs 64 a and 64 b. Of course, instead of having a singleflange 68 a, the reservoirs 24, 38, 40, 48, 44 a, 44 b, 56, would havetwo flanges projecting in opposite directions away from one another in adirection that is transverse to the length of the particular reservoiror reservoir segment that includes the flanges. In addition, thehousings used in reservoirs 24, 38, 40, 48, 44 a, 44 b, 56, and 58 maypreferably be configured so as not to be depressible, but instead, torupture when the corresponding pull tab is pulled. However, in certainexamples, the reservoirs of FIGS. 1-6 could be configured without a pulltab or string and with selectively depressible housings that function inthe same way that housings 65 a and 65 b function, i.e., such thatdepression of the housing ruptures the sealing membrane.

Referring to FIG. 14, another example of a bandage comprising aselectively releasable adhesion reducing material is provided. In thisexample, the bandage 71 includes at least one backing layer, a skinadhesive, and an adhesion reducing material layer, such that the atleast one backing layer is located between the adhesion reducingmaterial layer and the skin adhesive. In the particular example of FIG.14, the at least one backing layer includes a second backing layer suchthat the adhesion reducing material layer is sandwiched between thesecond backing layer and the first backing layer.

Bandage 71 comprises a first backing layer 75 and a second backing layer77. Backing layers 75 and 77 may be formed from the same materialsdescribed previously with respect to backing layer 22 of the previousembodiments. However, in certain examples, backing layers 75 and 77 arepreferably formed polymeric films. In certain examples, the polymericfilm is a polyethylene such s LDPE, LLDPE, MDPE, HDPE, UHMWPE. Thepolymeric films comprising backing layers 75 and 77 may comprise thesame or different materials. However, they are preferably heat sealableto one another at their respective edges. In certain examples, thesecond backing layer 77 has a thinner profile than first backing layer75 to provide greater adhesion reducing material layer actuationsensitivity. Other suitable polymeric films include those describedpreviously with respect to backing 22 and/or sealing membrane 70 a. Atleast the first backing layer 75 is preferably permeable to the adhesionreducing material, and in certain examples, both backing layers 75 and77 are permeable to the adhesion reducing material.

First backing layer 75 includes an upper surface 84 and a lower surface85. Backing layer 75 lower surface 85 comprises an absorbent pad 78 ofthe type described previously and a skin adhesive 92 separated into twosections along the length axis direction L of the first backing layer 75by the absorbent pad 78.

Upper surface 84 of lower backing layer 75 is connected to an adhesionreducing material layer which comprises a first adhesion reducingmaterial section 90 a and a second adhesion reducing material layersection 90 b. First adhesion reducing material section 90 a is spacedapart from second adhesion reducing material section 90 b in a directionalong the length axis direction L of lower backing layer 75. In certainpreferred examples, each adhesion reducing material layer section 90 aand 90 b is symmetrically disposed about the longitudinal midline ofbacking layer 75 (i.e., with its center at ½ of the backing layer 75width dimension in the width axis direction W). First adhesion reducingmaterial section 90 a is located in the first skin adhesive section 86 aof lower backing layer 75, while second adhesion reducing material layersection 90 b is located in the second skin adhesive section 86 c oflower backing layer 75. The first and second skin adhesive sections 86 aand 86 c are separated from one another by absorbent pad section 86 b.

Each adhesion reducing material layer section 90 a and 90 b comprises asynthetic or natural matrix impregnated with an adhesion reducingmaterial and which is capable of retaining the adhesion reducingmaterial until deformed by a bandage wearer. The deformation of theadhesion reducing material section 90 a and 90 b causes the adhesionreducing material to be released from the corresponding matrix,whereupon it can migrate through lower backing layer 75.

The synthetic or natural matrices comprising each of the adhesionreducing material layer sections 90 a and 90 b may comprise films,foams, woven or non-woven fabrics, or gauzes formed from syntheticand/or natural materials. In certain examples, the synthetic or naturalmatrices are resilient such that they remain in an undeformedconfiguration until a deforming force is applied and then return to theundeformed configuration when the deforming force is removed. Suitablefilms include medical grade absorbent films such as MEDCO 8106 absorbentpads with a porous polyethylene covering, and 3M Tegaderm pad/filmdressing with a non-adherent pad. Suitable foams include medical gradeabsorbent films such as flexible open cell polyurethane foams, re-bondedpolyurethane foams, reticulated polyurethane filtration foams, expandedclosed cell polyethylene foams, expanded closed cell crosslinkedpolyethylene foams, expanded EVA foams, expanded closed cell polystyrenefoams, anti-static, conductive, flocked and melamine foams, flamelaminated coated foams (tuftane, velcro fabric, aluminized mylar),closed cell neoprene & neoprene blend cellular materials, sponge rubbers(open and closed cell), and soft silicone. Suitable commerciallyavailable foams include Kendall® AMD foam dressing (Tyco Healthcare) andMepilex® Absorbent Foam Dressing (Molnlycke Health Care). Suitablegauzes include Invacare® Lodoform gauze packing strips and KendallVaseline® Petrolatum Gauze (Tyco Healthcare). The adhesion reducingmaterial layer sections may have a number of shapes and sizes. In theexample of FIG. 14, they comprise a synthetic or natural matrix materialcut into a generally cylindrical shape. The adhesion reducing materiallayer may comprise one or more adhesion reducing material layersections. In the case of plural adhesion reducing material layersections (as shown in FIG. 14), they may be spaced apart along thelength axis L direction and/or the width axis W direction as desired. Inaddition to using discrete and separate adhesion reducing material layersections, a single integral layer comprising a synthetic or naturaldeformable matrix impregnated with an adhesion reducing material mayalso be used.

In one example, the first and second backing layers 75 and 77 are bondedtogether to retain the first and section adhesion reducing materiallayer sections 90 a and 90 b between the backing layers 75 and 77.Bonding techniques such as heat sealing or adhesives may be used to holdthe backing layers 75 and 77 together.

In certain examples, the first adhesion reducing material section 90 aand second adhesion reducing material layer section 90 b are affixed tothe upper surface 84 of lower backing layer 75 by a suitable adhesive,preferably one that is not sensitive to contact with and which will notdegrade when contacted by the adhesion reducing material. In otherexamples, the bonding of the first and second backing layers 75 and 77is carried out in a way to securely hold the first and second adhesionreducing material layer sections 90 a and 90 b in place.

In additional examples, the lower backing layer 75 is formed withrecesses (not shown), such as cavities or dimples, that arecomplementarily sized to receive a portion of a respective one of thefirst and second adhesion reducing material layer sections 90 a and 90b. In such examples, the first and second adhesion reducing materiallayer sections 90 a and 90 b are preferably not completely enclosed inthe corresponding recesses but instead include a portion that projectsaway from lower backing layer 75 upper surface 84 to facilitatedeformation by the user when desired.

In certain implementations, an adhesive may be applied to the interiorof the recesses to more securely hold the adhesion reducing materiallayer sections 90 a and 90 b in place. One advantage to using a recesseddesign is that in some instances the overall thickness profile (i.e.,the thickness in a direction orthogonal to the length axis direction Land width axis direction W) can be reduced relative to designs in whichthe adhesion reducing material layer sections 90 a and 90 b areconnected to the lower backing layer 75 surface at a point of contactthat is flush with the remainder of the lower backing layer 75. Incertain preferred examples in which such recesses are employed, theupper backing layer 77 is bonded to the lower backing layer 75 usingtechniques such as heat sealing or adhesive bonding to further securethe adhesion reducing material layer sections 90 a and 90 b.

In certain cases—especially those in which the adhesion reducingmaterial layer sections 90 a and 90 b are held in recesses formed inlower backing layer 75—it may be desirable to print markings, graphic,or other indicia on the upper backing layer 77 immediately over theadhesion reducing material layer sections 90 a and 90 b so a bandagewearer can more accurately direct a deformation force to the sections 90a and 90 b to release the adhesion reducing material.

Bandage 71 will typically be applied to the wearer's body with absorbentpad 78 in contact with a skin trauma and skin adhesive 92 in contactwith portions of the wearer's skin adjacent the skin trauma. When thewearer wishes to remove the bandage 71, he or she will depress the upperbacking layer 77 at a position along the length L and width W directionthat corresponds to the location of the adhesion reducing material layersections 90 a and 90 b along the length L and width direction W. Thedepression of upper backing layer 77 will cause the correspondingadhesion reducing material section 90 a and 90 b to deform, therebyreleasing the adhesion reducing material from its synthetic or naturalmatrix. The released adhesion reducing material then migrates throughthe lower backing layer 75 to contact the skin adhesive 92 and reduceits adhesive force on the wearer's skin.

In certain examples wherein upper backing layer 77 is permeable to theadhesion reducing material, the adhesion reducing material may squeezeout away from the position of the adhesion reducing material layersections 90 a and 90 b and migrate to the upper surface 80 of upperbacking layer 77 laterally of the adhesion reducing material layersections 90 a and 90 b, allowing the user to spread the adhesionreducing material over the upper surface 80 of upper backing layer 77 infirst skin adhesive section 86 a and second skin adhesive region 86 c.Spreading of the adhesion reducing material in this manner allows thematerial to then migrate through the upper backing layer 77 and lowerbacking layer 75 and increases the area of contact between the skinadhesive 92 and the adhesion reducing material. After selectivelyreleasing the adhesion reducing material from adhesion reducing materiallayer sections 90 a and 90 b in this manner, the user can then peel thebandage from his or her skin.

In those examples in which the adhesion reducing material layer sections90 a and 90 b are held in recesses formed in first backing layer 75, itwould be possible to simply load the adhesion reducing material in therecesses and then seal the lower backing layer 75 with the upper backinglayer 77, thereby avoiding the need for the adhesion reducing materiallayer sections 90 a and 90 b altogether. The wearer could then rupturethe recesses to release the adhesion reducing material. However, the useof first deformable synthetic or natural matrices as the sections 90 aand 90 b achieves several advantages over such a design. For example, ifthe adhesion reducing material were provided in backing layer recesses,the first backing layer 75 would likely have to be occlusive(non-permeable) to the adhesion reducing material to prevent leakage.Upper backing layer 77 would similarly have to be occlusive to preventthe fluid from leaking from the recesses through upper backing layer 77.In addition, the adhesion reducing material could tend to leak out ofthe bandage from between the two backing layers 75 and 77. Because thedeformable synthetic or natural matrices allow for the use of permeablebacking layers 75 and 77, the released adhesion reducing material can besqueezed back through the backing layers 75 and 77, allowing the wearerto spread it over the surface area of upper backing layer 77 in the skinadhesive sections 86 a and 86 c, causing the material to migrate backthrough the backing layers 77 and 75 to the skin adhesive 92 and therebyproviding a greater contact surface area between the adhesion reducingmaterial and the skin adhesive 92.

In certain examples, the amount of adhesion reducing material held inthe first and second adhesion reducing material sections 90 a and 90 bis related to or proportional to the surface area of the lower backinglayer 75 lying within the skin adhesive sections 86 a and 86 c. Incertain examples, the volume per unit surface area of skin adhesivesections 86 a and 86 c on lower backing layer upper surface 84 ispreferably at least about 1.2 μl/cm², more preferably at least about 1.8μl/cm², and still more preferably at least about 2.0 μl/cm². At the sametime or in other examples, the volume per unit surface area ispreferably not more than about 4.6 μl/cm², more preferably not more thanabout 3.4 μl/cm², and still more preferably not more than about 2.5μl/cm². In one example, the volume of adhesion reducing material perunit surface area of lower backing layer upper surface 84 in the skinadhesive regions 26 a and 26 c is about 2.3 μl/cm².

A method of using the bandage 71 will now be described. To protect askin trauma, the user first removes a release liner (not shown) fromlower backing layer 75 lower side 85 which covers the skin adhesive 92and absorbent pad 78 as in the case of a standard bandage. The absorbentpad 78 is then placed in contact with the skin trauma to protect it andabsorb any fluids associated with it. The portions of lower surface 85of first backing layer 75 lying within the skin adhesive sections 86 aand 86 c are then placed in contact with the skin on either side of theskin trauma to affix the bandage to the wearer.

After a desired period of use, the wearer then removes the bandage bydepressing the upper backing layer 77 at first location along the lengthand width axis directions that is aligned with a first selected one ofthe adhesion reducing material layer sections 90 a or 90 b. Thedepression of the upper backing layer causes the first and secondadhesion reducing material layer sections 90 a or 90 b to release theadhesion reducing material. The adhesion reducing material travelsacross the upper surface 84 of lower backing layer 75 and thenpenetrates the lower backing layer 75 to come into contact with skinadhesive 92 on lower surface 85 of lower backing layer 75. In certainexamples, the points of attachment between the adhesion reducingmaterial layer sections 90 a and 90 b and upper surface 84 of lowerbacking layer 75 are occluded to prevent premature leakage of theadhesion reducing material through the lower backing layer 87 at thepoints of attachment.

The wearer then selects a second one of the first and second adhesionreducing material sections 90 a and 90 b and depresses the upper backinglayer 77 at a location that is aligned with the selected second one ofthe first and second adhesion reducing material sections 90 a and 90 b,causing the first and second adhesion reducing material layer sections90 a or 90 b to release the adhesion reducing material.

If the lower backing layer 75 and upper backing layer 77 are permeableto the adhesion reducing material, some amount of it will likelypenetrate the upper backing layer 77 following deformation of theadhesion reducing material layer sections 90 a and 90 b. The wearer canthen use his or her fingers or a suitable instrument to spread theadhesion reducing material along the upper surface 80 of upper backinglayer 77 to cover a desired portion of the upper surface 80 lying withinthe skin adhesive sections 86 a and 86 c. The adhesion reducing materialwill then penetrate back through the upper backing layer 77 and lowerbacking layer 75 to contact skin adhesive 92 and weaken its adhesion tothe wearer's skin. The wearer can then grip the underside of the lowerbacking layer 75 and peel the bandage off of his or her skin.

A method of making the bandage 71 of FIG. 14 will now be described. Inaccordance with a first exemplary method, sheets of material used toform first backing layer 75 are provided and are coated with a skinadhesive 92 on one side. The backing layer material is then cut intostrips and the absorbent material used to form absorbent pads 78 is cutinto strips. Using standard bandage making machinery, the absorbent padmaterial strips are adhesively adhered to a central portion of thestrips of backing layer 75 material such that there is a portion ofbacking on either side of the absorbent pad strips.

The combined backing/absorbent pad strips are then recessed on the sideof the backing strips opposite the absorbent pad material. Impregnatedfirst and second adhesion reducing material sections are adhesivelyattached in the recesses. In those examples where lower backing layer 75is not recessed, the first and second adhesion reducing materialsections are adhesive attached to the surface of the backing stripsopposite the absorbent pad.

The material used to form upper backing layer 77 is formed into stripshaving a width similar to the width of the strips of lower backing layer75 material. The upper backing layer material 77 is affixed to the lowerbacking material layer using adhesives, heat sealing and/or pressurethereby forming long strips of assembled bandage material which can thenbe cut width-wise to yield the final bandages. A release liner with asuitable release coating is placed over the skin adhesive 92 andabsorbent pad 78, and the bandages are packaged and sterilized usingknown techniques, which are preferably selected so as not to degrade orcause the premature release of the absorbent reducing material from thefirst and second adhesion reducing material sections 90 a and 90 b.

The present invention has been described with reference to certainexemplary embodiments thereof. However, it will be readily apparent tothose skilled in the art that it is possible to embody the invention inspecific forms other than those of the exemplary embodiments describedabove. This may be done without departing from the spirit of theinvention. The exemplary embodiments are merely illustrative and shouldnot be considered restrictive in any way. The scope of the invention isdefined by the appended claims and their equivalents, rather than by thepreceding description.

1. A bandage comprising: a backing layer having a first side and asecond side; a skin adhesive on the backing layer first side, at leastone selectively rupturable reservoir on the backing layer second side;and an adhesion reducing material, wherein the at least one selectivelyrupturable reservoir comprises a housing and a sealing membrane, and thehousing and the sealing membrane define an enclosed interior containingthe adhesion reducing material.
 2. The bandage of claim 1, wherein thehousing projects away from the second backing side.
 3. The bandage ofclaim 1, wherein the sealing membrane is selectively rupturable torupture the reservoir.
 4. The bandage of claim 3, wherein the housing isselectively deformable and has a sealing configuration and a releasingconfiguration, such that when a user deforms the selectively deformablehousing to the releasing configuration, the sealing membrane ruptures.5. The bandage of claim 1, wherein the bandage further comprises a pullstring engaging the housing, the pull string has a sealing position anda rupturing position, and when a user pulls the pull string from thesealing position to the rupturing position, the housing ruptures torelease the adhesion reducing material.
 6. The bandage of claim 1,wherein the housing comprises a polyethylene material.
 7. The bandage ofclaim 1, wherein the at least one selectively rupturable reservoircomprises a plurality of dome-shaped selectively rupturable reservoirs.8. The bandage of claim 1, wherein the bandage has a backing with alength, and the at least one selectively rupturable reservoir comprisesa single selectively rupturable reservoir extending along the length ofthe backing.
 9. The bandage of claim 1, wherein the bandage has anabsorbent pad on the backing layer first side defining an absorbent padregion on the backing, and the at least one selectively rupturablereservoir is located outside of the absorbent pad region.
 10. Thebandage of claim 1, wherein at least one selectively rupturablereservoir comprises a plurality of linear segments in fluidcommunication with one another.
 11. The bandage of claim 1, wherein thebacking layer has a length and a width, and the at least one selectivelyrupturable reservoir comprises two selectively rupturable reservoirsspaced apart from one another along the backing layer length such thateach selectively rupturable reservoir extends along the backing layerwidth.
 12. The bandage of claim 1, wherein the backing layer has alength and a width, and the at least one selectively rupturablereservoir comprises a single selectively rupturable reservoir, a firstportion of the single selectively rupturable reservoir extends along thebacking layer length, and a second portion of the single selectivelyrupturable reservoir extends along the backing layer width.
 13. Thebandage of claim 1, wherein the backing layer is permeable such that theadhesion reducing material can penetrate from the backing layer secondside to the backing layer first side.
 14. The bandage of claim 1,wherein the adhesion reducing material comprises at least one selectedfrom a liquid and a semi-solid.
 15. The bandage of claim 14, wherein theadhesion reducing material comprises a plant extract.
 16. The bandage ofclaim 14, wherein the adhesion reducing material comprises an animalextract.
 17. The bandage of claim 14, wherein the adhesion reducingmaterial comprises a petroleum extract.
 18. The bandage of claim 14,wherein the adhesion reducing material comprises water.
 19. The bandageof claim 1, wherein the housing comprises a dome portion, at least oneflange portion, the flange portion is attached to the backing layersecond side, and a portion of the sealing membrane periphery is disposedbetween the at least one flange portion and the backing layer secondside.
 20. The bandage of claim 19, wherein the housing is circular whenviewed from a top plan view, and the at least one flange portion is asingle flange portion extending around the dome portion.
 21. A method ofremoving the bandage of claim 1, wherein the skin adhesive is adhered tothe wearer's skin, the method comprising: selectively rupturing theselectively rupturable reservoir, thereby releasing the adhesionreducing material from the selectively rupturable reservoir; and peelingthe backing from the wearer's skin.
 22. The method of claim 21, whereinthe bandage includes an absorbent pad on the backing layer first sidesuch that when the skin adhesive is adhered to the wearer's skin, theabsorbent pad is in contact with a skin trauma.
 23. The method of claim21, further comprising applying the released adhesion reducing materialacross the backing layer second side.
 24. A method of removing thebandage of claim 1, wherein the skin adhesive is adhered to the wearer'sskin, the bandage further comprises a pull string engaging the housing,the pull string has a sealing position and a rupturing position, thehousing ruptures to release the adhesion reducing material, and themethod further comprises: pulling the string from the sealing positionto the rupturing position to thereby rupture the housing; and peelingthe backing from the wearer's skin.
 25. A method of removing the bandageof claim 1, wherein the skin adhesive is adhered to the wearer's skin,the method further comprising: deforming the housing from a sealingconfiguration to a releasing configuration, such that the sealingmembrane ruptures; and peeling the backing from the wearer's skin.
 26. Abandage, comprising: a first backing layer having a first side and asecond side; a skin adhesive on the first backing layer first side; atleast one adhesion reducing material matrix on the first backing layersecond side, wherein the adhesion reducing material matrix isimpregnated with an adhesion reducing material and has a retainingconfiguration and a releasing configuration; a second backing layerhaving a first side and a second side, wherein the second backing layerfirst side faces the first backing layer second side.
 27. The bandage ofclaim 26, wherein the at least one adhesion reducing material matrixcomprises one selected from a film, a foam, and a gauze, and when the atleast one adhesion reducing material matrix is deformed from theretaining configuration to the releasing configuration, the adhesionreducing material is released from the adhesion reducing materialmatrix.
 28. The bandage of claim 26, wherein the at least one adhesionreducing material matrix is resilient.
 29. The bandage of claim 26,wherein the first backing layer second side comprises at least onerecess, and the at least one adhesion reducing material matrix isdisposed in the at least one recess.
 30. The bandage of claim 26,wherein at least a perimeter portion of the first backing layer isattached to at least a perimeter portion of the second backing layer.31. The bandage of claim 26, wherein the at least one adhesion reducingmaterial matrix projects away from the first backing layer second side.32. The bandage of claim 26, wherein the at least one adhesion reducingmaterial matrix comprises two adhesion reducing material matrices, thebandage includes an absorbent pad on the first backing layer first side,the first backing layer includes an absorbent pad region, and the twoadhesion reducing material matrices are located outside of the absorbentpad region.
 33. The bandage of claim 26, wherein the first backing layeris permeable to the adhesion reducing material.
 34. The bandage of claim33, wherein the second backing layer is permeable to the adhesionreducing material.
 35. The bandage of claim 26, wherein the adhesionreducing material comprises at least one selected from a liquid and asemi-solid.
 36. The bandage of claim 35, wherein the adhesion reducingmaterial comprises a plant extract.
 37. The bandage of claim 35, whereinthe adhesion reducing material comprises an animal extract.
 38. Thebandage of claim 35, wherein the adhesion reducing material comprises apetroleum extract.
 39. The bandage of claim 35, wherein the adhesionreducing material comprises water.
 40. A method of removing the bandageof claim 26, wherein the first backing layer skin adhesive is adhered tothe wearer's skin, the method comprising: deforming the at least oneadhesion reducing material matrix to release the adhesion reducingmaterial; and peeling the first backing layer from the wearer's skin.41. The method of claim 40, wherein the step of deforming the at leastone adhesion reducing material matrix comprises pressing the secondbacking layer.
 42. The method of claim 40, wherein the bandage includesan absorbent pad on the first backing side such that when the skinadhesive is adhered to the wearer's skin, the absorbent pad is incontact with a skin trauma.